<?php
// +----------------------------------------------------------------------
// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]
// +----------------------------------------------------------------------
// | Copyright (c) 2006-2012 http://thinkphp.cn All rights reserved.
// +----------------------------------------------------------------------
// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
// +----------------------------------------------------------------------
// | Author: liu21st <liu21st@gmail.com>
// +----------------------------------------------------------------------
// $Id: RelationModel.class.php 2702 2012-02-02 12:35:01Z liu21st $

/**
 +------------------------------------------------------------------------------
 * ThinkPHP 关联模型类扩展
 +------------------------------------------------------------------------------
 */
define('HAS_ONE',1);
define('BELONGS_TO',2);
define('HAS_MANY',3);
define('MANY_TO_MANY',4);

class RelationModel extends Model {
	// 关联定义
	protected    $_link = array();

	/**
	 +----------------------------------------------------------
	 * 动态方法实现
	 +----------------------------------------------------------
	 * @access public
	 +----------------------------------------------------------
	 * @param string $method 方法名称
	 * @param array $args 调用参数
	 +----------------------------------------------------------
	 * @return mixed
	 +----------------------------------------------------------
	 */
	public function __call($method,$args) {
		if(strtolower(substr($method,0,8))=='relation'){
			$type    =   strtoupper(substr($method,8));
			if(in_array($type,array('ADD','SAVE','DEL'),true)) {
				array_unshift($args,$type);
				return call_user_func_array(array(&$this, 'opRelation'), $args);
			}
		}else{
			return parent::__call($method,$args);
		}
	}

	/**
	 +----------------------------------------------------------
	 * 得到关联的数据表名
	 +----------------------------------------------------------
	 * @access public
	 +----------------------------------------------------------
	 * @return string
	 +----------------------------------------------------------
	 */
	public function getRelationTableName($relation) {
		$relationTable  = !empty($this->tablePrefix) ? $this->tablePrefix : '';
		$relationTable .= $this->tableName?$this->tableName:$this->name;
		$relationTable .= '_'.$relation->getModelName();
		return strtolower($relationTable);
	}

	// 查询成功后的回调方法
	protected function _after_find(&$result,$options) {
		// 获取关联数据 并附加到结果中
		if(!empty($options['link']))
		$this->getRelation($result,$options['link']);
	}

	// 查询数据集成功后的回调方法
	protected function _after_select(&$result,$options) {
		// 获取关联数据 并附加到结果中
		if(!empty($options['link']))
		$this->getRelations($result,$options['link']);
	}

	// 写入成功后的回调方法
	protected function _after_insert($data,$options) {
		// 关联写入
		if(!empty($options['link']))
		$this->opRelation('ADD',$data,$options['link']);
	}

	// 更新成功后的回调方法
	protected function _after_update($data,$options) {
		// 关联更新
		if(!empty($options['link']))
		$this->opRelation('SAVE',$data,$options['link']);
	}

	// 删除成功后的回调方法
	protected function _after_delete($data,$options) {
		// 关联删除
		if(!empty($options['link']))
		$this->opRelation('DEL',$data,$options['link']);
	}

	/**
	 +----------------------------------------------------------
	 * 对保存到数据库的数据进行处理
	 +----------------------------------------------------------
	 * @access protected
	 +----------------------------------------------------------
	 * @param mixed $data 要操作的数据
	 +----------------------------------------------------------
	 * @return boolean
	 +----------------------------------------------------------
	 */
	protected function _facade($data) {
		$this->_before_write($data);
		return $data;
	}

	/**
	 +----------------------------------------------------------
	 * 获取返回数据集的关联记录
	 +----------------------------------------------------------
	 * @access protected
	 +----------------------------------------------------------
	 * @param array $resultSet  返回数据
	 * @param string|array $name  关联名称
	 +----------------------------------------------------------
	 * @return array
	 +----------------------------------------------------------
	 */
	protected function getRelations(&$resultSet,$name='') {
		// 获取记录集的主键列表
		foreach($resultSet as $key=>$val) {
			$val  = $this->getRelation($val,$name);
			$resultSet[$key]    =   $val;
		}
		return $resultSet;
	}

	/**
	 +----------------------------------------------------------
	 * 获取返回数据的关联记录
	 +----------------------------------------------------------
	 * @access protected
	 +----------------------------------------------------------
	 * @param mixed $result  返回数据
	 * @param string|array $name  关联名称
	 * @param boolean $return 是否返回关联数据本身
	 +----------------------------------------------------------
	 * @return array
	 +----------------------------------------------------------
	 */
	protected function getRelation(&$result,$name='',$return=false) {
		if(!empty($this->_link)) {
			foreach($this->_link as $key=>$val) {
				$mappingName =  !empty($val['mapping_name'])?$val['mapping_name']:$key; // 映射名称
				if(empty($name) || true === $name || $mappingName == $name || (is_array($name) && in_array($mappingName,$name))) {
					$mappingType = !empty($val['mapping_type'])?$val['mapping_type']:$val;  //  关联类型
					$mappingClass  = !empty($val['class_name'])?$val['class_name']:$key;            //  关联类名
					$mappingFields = !empty($val['mapping_fields'])?$val['mapping_fields']:'*';     // 映射字段
					$mappingCondition = !empty($val['condition'])?$val['condition']:'1=1';          // 关联条件
					if(strtoupper($mappingClass)==strtoupper($this->name)) {
						// 自引用关联 获取父键名
						$mappingFk   =   !empty($val['parent_key'])? $val['parent_key'] : 'parent_id';
					}else{
						$mappingFk   =   !empty($val['foreign_key'])?$val['foreign_key']:strtolower($this->name).'_id';     //  关联外键
					}
					// 获取关联模型对象
					$model = D($mappingClass);
					switch($mappingType) {
						case HAS_ONE:
							$pk   =  $result[$this->getPk()];
							$mappingCondition .= " AND {$mappingFk}='{$pk}'";
							$relationData   =  $model->where($mappingCondition)->field($mappingFields)->find();
							break;
						case BELONGS_TO:
							if(strtoupper($mappingClass)==strtoupper($this->name)) {
								// 自引用关联 获取父键名
								$mappingFk   =   !empty($val['parent_key'])? $val['parent_key'] : 'parent_id';
							}else{
								$mappingFk   =   !empty($val['foreign_key'])?$val['foreign_key']:strtolower($model->getModelName()).'_id';     //  关联外键
							}
							$fk   =  $result[$mappingFk];
							$mappingCondition .= " AND {$model->getPk()}='{$fk}'";
							$relationData   =  $model->where($mappingCondition)->field($mappingFields)->find();
							break;
						case HAS_MANY:
							$pk   =  $result[$this->getPk()];
							$mappingCondition .= " AND {$mappingFk}='{$pk}'";
							$mappingOrder =  !empty($val['mapping_order'])?$val['mapping_order']:'';
							$mappingLimit =  !empty($val['mapping_limit'])?$val['mapping_limit']:'';
							// 延时获取关联记录
							$relationData   =  $model->where($mappingCondition)->field($mappingFields)->order($mappingOrder)->limit($mappingLimit)->select();
							break;
						case MANY_TO_MANY:
							$pk   =  $result[$this->getPk()];
							$mappingCondition = " {$mappingFk}='{$pk}'";
							$mappingOrder =  $val['mapping_order'];
							$mappingLimit =  $val['mapping_limit'];
							$mappingRelationFk = $val['relation_foreign_key']?$val['relation_foreign_key']:$model->getModelName().'_id';
							$mappingRelationTable  =  $val['relation_table']?$val['relation_table']:$this->getRelationTableName($model);
							if ($val['auto_prefix']) {
								$mappingRelationTable = $this->tablePrefix . $mappingRelationTable;
							}
							$sql = "SELECT b.{$mappingFields} FROM {$mappingRelationTable} AS a, ".$model->getTableName()." AS b WHERE a.{$mappingRelationFk} = b.{$model->getPk()} AND a.{$mappingCondition}";
							if(!empty($val['condition'])) {
								$sql   .= ' AND '.$val['condition'];
							}
							if(!empty($mappingOrder)) {
								$sql .= ' ORDER BY '.$mappingOrder;
							}
							if(!empty($mappingLimit)) {
								$sql .= ' LIMIT '.$mappingLimit;
							}
							$relationData   =   $this->query($sql);
							break;
					}
					if(!$return){
						if(isset($val['as_fields']) && in_array($mappingType,array(HAS_ONE,BELONGS_TO)) ) {
							// 支持直接把关联的字段值映射成数据对象中的某个字段
							// 仅仅支持HAS_ONE BELONGS_TO
							$fields =   explode(',',$val['as_fields']);
							foreach ($fields as $field){
								if(strpos($field,':')) {
									list($name,$nick) = explode(':',$field);
									$result[$nick]  =  $relationData[$name];
								}else{
									$result[$field]  =  $relationData[$field];
								}
							}
						}else{
							$result[$mappingName] = $relationData;
						}
						unset($relationData);
					}else{
						return $relationData;
					}
				}
			}
		}
		return $result;
	}

	/**
	 +----------------------------------------------------------
	 * 操作关联数据
	 +----------------------------------------------------------
	 * @access protected
	 +----------------------------------------------------------
	 * @param string $opType  操作方式 ADD SAVE DEL
	 * @param mixed $data  数据对象
	 * @param string $name 关联名称
	 +----------------------------------------------------------
	 * @return mixed
	 +----------------------------------------------------------
	 */
	protected function opRelation($opType,$data='',$name='') {
		$result =   false;
		if(empty($data) && !empty($this->data)){
			$data = $this->data;
		}elseif(!is_array($data)){
			// 数据无效返回
			return false;
		}
		if(!empty($this->_link)) {
			// 遍历关联定义
			foreach($this->_link as $key=>$val) {
				// 操作制定关联类型
				$mappingName =  $val['mapping_name']?$val['mapping_name']:$key; // 映射名称
				if(empty($name) || true === $name || $mappingName == $name || (is_array($name) && in_array($mappingName,$name)) ) {
					// 操作制定的关联
					$mappingType = !empty($val['mapping_type'])?$val['mapping_type']:$val;  //  关联类型
					$mappingClass  = !empty($val['class_name'])?$val['class_name']:$key;            //  关联类名
					// 当前数据对象主键值
					$pk =   $data[$this->getPk()];
					if(strtoupper($mappingClass)==strtoupper($this->name)) {
						// 自引用关联 获取父键名
						$mappingFk   =   !empty($val['parent_key'])? $val['parent_key'] : 'parent_id';
					}else{
						$mappingFk   =   !empty($val['foreign_key'])?$val['foreign_key']:strtolower($this->name).'_id';     //  关联外键
					}
					$mappingCondition = !empty($val['condition'])?  $val['condition'] :  "{$mappingFk}='{$pk}'";
					// 获取关联model对象
					$model = D($mappingClass);
					$mappingData    =   isset($data[$mappingName])?$data[$mappingName]:false;
					if(!empty($mappingData) || $opType == 'DEL') {
						switch($mappingType) {
							case HAS_ONE:
								switch (strtoupper($opType)){
									case 'ADD': // 增加关联数据
										$mappingData[$mappingFk]    =   $pk;
										$result   =  $model->add($mappingData);
										break;
									case 'SAVE':    // 更新关联数据
										$result   =  $model->where($mappingCondition)->save($mappingData);
										break;
									case 'DEL': // 根据外键删除关联数据
										$result   =  $model->where($mappingCondition)->delete();
										break;
								}
								break;
							case BELONGS_TO:
								break;
							case HAS_MANY:
								switch (strtoupper($opType)){
									case 'ADD'   :  // 增加关联数据
										$model->startTrans();
										foreach ($mappingData as $val){
											$val[$mappingFk]    =   $pk;
											$result   =  $model->add($val);
										}
										$model->commit();
										break;
									case 'SAVE' :   // 更新关联数据
										$model->startTrans();
										$pk   =  $model->getPk();
										foreach ($mappingData as $vo){
											if(isset($vo[$pk])) {// 更新数据
												$mappingCondition   =  "$pk ={$vo[$pk]}";
												$result   =  $model->where($mappingCondition)->save($vo);
											}else{ // 新增数据
												$vo[$mappingFk] =  $data[$this->getPk()];
												$result   =  $model->add($vo);
											}
										}
										$model->commit();
										break;
									case 'DEL' :    // 删除关联数据
										$result   =  $model->where($mappingCondition)->delete();
										break;
								}
								break;
							case MANY_TO_MANY:
								$mappingRelationFk = $val['relation_foreign_key']?$val['relation_foreign_key']:$model->getModelName().'_id';// 关联
								$mappingRelationTable  =  $val['relation_table']?$val['relation_table']:$this->getRelationTableName($model);
								if ($val['auto_prefix']) {
									$mappingRelationTable = $this->tablePrefix . $mappingRelationTable;
								}
								if(is_array($mappingData)) {
									$ids   = array();
									foreach ($mappingData as $vo)
									$ids[]   =   $vo[$model->getPk()];
									$relationId =   implode(',',$ids);
								}
								switch (strtoupper($opType)){
									case 'ADD': // 增加关联数据
									case 'SAVE':    // 更新关联数据
										if(isset($relationId)) {
											$this->startTrans();
											// 删除关联表数据
											$this->table($mappingRelationTable)->where($mappingCondition)->delete();
											// 插入关联表数据
											$sql  = 'INSERT INTO '.$mappingRelationTable.' ('.$mappingFk.','.$mappingRelationFk.') SELECT a.'.$this->getPk().',b.'.$model->getPk().' FROM '.$this->getTableName().' AS a ,'.$model->getTableName()." AS b where a.".$this->getPk().' ='. $pk.' AND  b.'.$model->getPk().' IN ('.$relationId.") ";
											$result =   $model->execute($sql);
											if(false !== $result)
											// 提交事务
											$this->commit();
											else
											// 事务回滚
											$this->rollback();
										}
										break;
									case 'DEL': // 根据外键删除中间表关联数据
										$result =   $this->table($mappingRelationTable)->where($mappingCondition)->delete();
										break;
								}
								break;
						}
					}
				}
			}
		}
		return $result;
	}

	/**
	 +----------------------------------------------------------
	 * 进行关联查询
	 +----------------------------------------------------------
	 * @access public
	 +----------------------------------------------------------
	 * @param mixed $name 关联名称
	 +----------------------------------------------------------
	 * @return Model
	 +----------------------------------------------------------
	 */
	public function relation($name) {
		$this->options['link']  =   $name;
		return $this;
	}

	/**
	 +----------------------------------------------------------
	 * 关联数据获取 仅用于查询后
	 +----------------------------------------------------------
	 * @access public
	 +----------------------------------------------------------
	 * @param string $name 关联名称
	 +----------------------------------------------------------
	 * @return array
	 +----------------------------------------------------------
	 */
	public function relationGet($name) {
		if(empty($this->data))
		return false;
		return $this->getRelation($this->data,$name,true);
	}
}